﻿Shader "UI/ImageGary" {
	Properties{
		[PerRendererData] _MainTex("Sprite Texture",2D) = "White"{ }
		_GrayMultiplyColor("Convert Factors",Color)=(0.299,0.587,0.114,1)
		_GrayFactor("Gray Factors",Range(0,1))=1

		[HideInInspector]_StencilComp("Stencil Comparison",Float) = 8
		[HideInInspector]_Stencil("Stencil ID",Float) = 0
		[HideInInspector]_StencilOp("Stencil Operation",Float)=0
		[HideInInspector]_StencilWriteMask("Stencil Write Mask",Float) = 255
		[HideInInspector]_StencilReadMask("Stencil Read Mask",Float) = 255
		[HideInInspector]_ColorMask("Color Mask",Float) = 15

		[Toggle(UNITY_UI_ALPHACLIP)] _UseUIAlphaClip("Use Alpha Clip",Float) = 0
	}
		SubShader{
		Tags
	{
		"Queue" = "Transparent"
		"IgnoreProjector" = "True"
		"RenderType" = "Transparent"
		"PreviewType" = "Plane"
		"CanUseSpriteAtlas" = "True"
	}
		Stencil
	{
		Ref[_Stencil]
		Comp[_StencilComp]
		Pass[_StencilOp]
		ReadMask[_StencilReadMask]
		WriteMask[_StencilWriteMask]
	}
		Cull Off
		Lighting Off
		ZWrite Off
		ZTest[unity_GUIZTestMode]
		Blend SrcAlpha OneMinusSrcAlpha
		ColorMask[_ColorMask]

		Pass{
		Name "UIImage_Static_Gray"
		CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma target 2.0

#include "UnityCG.cginc"
#include "UnityUI.cginc"

#pragma multi_compile __ UNITY_UI_ALPHACLIP

		struct appdata_t {
		float4 vertex : POSITION;
		float4 color : COLOR;
		float2 texcoord : TEXCOORD0;
		UNITY_VERTEX_INPUT_INSTANCE_ID
	};
	struct v2f {
		float4 vertex : SV_POSITION;
		fixed4 color : COLOR;
		half2 texcoord : TEXCOORD0;
		float4 worldPosition : TEXCOORD1;
		UNITY_VERTEX_OUTPUT_STEREO
	};
	uniform sampler2D _MainTex;
	uniform fixed4 _TextureSampleAdd;
	uniform fixed4 _ClipRect;
	uniform float4 _GrayMultiplyColor;
	uniform float _GrayFactor;

	v2f vert(appdata_t IN) {
		v2f OUT;
		UNITY_SETUP_INSTANCE_ID(IN);
		UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(OUT);
		OUT.worldPosition = IN.vertex;
		OUT.vertex = UnityObjectToClipPos(OUT.worldPosition);

		OUT.texcoord = IN.texcoord;

		OUT.color = IN.color;
		return OUT;
	}

	fixed4 frag(v2f IN) : SV_Target{
		float4  colMain = tex2D(_MainTex,IN.texcoord);
		float grayColor = colMain.r * _GrayMultiplyColor.x + colMain.g * _GrayMultiplyColor.y +colMain.b * _GrayMultiplyColor.z;
		fixed4 color = lerp(colMain,float4 (grayColor,grayColor,grayColor,1.0),_GrayFactor);
		color.a = colMain.a;

		color.a *= UnityGet2DClipping(IN.worldPosition.xy,_ClipRect);

		#ifdef UNITY_UI_ALPHACLIP
		clip(color.a - 0.001);
		#endif

		return color;
	}
		ENDCG
	}
	}
}

